KR100952421B1 - Filter element for cleaning inlet air of internal combustion engine and process for preparing the same - Google Patents

Abstract

The present invention relates to a filter medium for purifying the inlet air of an internal combustion engine that can effectively purify contaminants and the like from the air in the atmosphere and to a method of manufacturing the same. More specifically, the present invention comprises two or more layers having a density gradient. Filter media for air purification comprising at least one spunbond nonwoven fabric fiber layer and a filter paper layer or meltblown as a final layer on the outlet side of the fluid, particularly preferably a meltblown layer composed of two or more components having different melting temperatures and It relates to a manufacturing method. The filter media can improve the life (capture amount) decrease, which is a problem when using the filter paper alone, and can increase the efficiency, which is a problem of the nonwoven filter.

Filters, Spunbond, Melt Blown

Description

Filter element for cleaning inlet air of internal combustion engine and its manufacturing method {Filter element for cleaning inlet air of internal combustion engine and process for preparing the same}

1 is a schematic view showing one embodiment of a process for producing a filter material for air purification according to the present invention.

Figure 2 is a schematic view showing another embodiment of the manufacturing process of the filter material for air purification according to the present invention.

Figure 3 is a schematic diagram showing another embodiment of the air purification media according to the present invention.

Figure 4 is a schematic view showing another embodiment of the air purifying medium according to the present invention.

5 is a schematic view showing another embodiment of the air purifying medium according to the present invention.

The present invention relates to a filter medium for purifying the inlet air of an internal combustion engine that can effectively purify contaminants and the like from the air in the atmosphere and to a method of manufacturing the same. More specifically, the present invention comprises two or more layers having a density gradient. A filter media for air purification comprising at least one spunbond nonwoven fabric fiber layer and a filter paper layer or a meltblown layer as a final layer on the outlet side of the fluid, and a method of manufacturing the same.

In general, an engine of an internal combustion engine drives an engine by supplying liquefied fuel such as gasoline or diesel oil and gaseous fuel such as LPG. The fuel is supplied into a combustion chamber in the form of a mixed gas mixed with oxygen in air to cause a combustion explosion. . At this time, the air in the air flowing into the engine to make the mixed gas is mixed with foreign substances such as dust, which causes incomplete combustion, making it difficult to operate the vehicle or equipment and at the same time, foreign substances are introduced into the engine and paired with the cylinder wall of the engine. This brings about a problem of lowering the durability of the engine. In addition, recently developed internal combustion engines are equipped with a device that measures the amount of air required, and fine carbon (soot) present in the air contaminates the sensor, reducing the engine output.

In a conventional automobile engine, the air cleaner is equipped with an air filtration medium, and the oil filter is equipped with an oil filtration medium to remove impurities contained in lubricating oil contained in the engine.

In these filter media, various kinds of filter papers, which are technically designed according to the size and amount of the substance to remove various foreign substances, are mounted as the filter medium. These filter media must satisfy the filtration efficiency and sufficient filtration life to filter out impurities in order to sufficiently provide the flow and amount of air or lubricating oil required while the engine is running.

However, in order to actually manufacture the filter medium so as to sufficiently collect impurities, the vent holes of the filter medium need to be finely formed so that the vent holes are clogged quickly. That is, such a medium has a disadvantage in that it can not be used for a long time, on the contrary, if a large air vent is formed, all fine dust escapes and the filtration efficiency is poor. Therefore, it is necessary to design a medium that can satisfy both the filtration efficiency and the lifetime.

Currently, filter papers and nonwoven fabrics are mainly used as filter materials for automobiles. Filter papers are prepared by a process of dissolving, beating, papermaking, impregnating, drying, and winding appropriately blending natural pulp and synthetic fibers, depending on the application. There are many kinds of nonwoven fabrics, such as spunbond, spunlace, chemical bond, thermal bond, needle punching, and meltblown, depending on the method of manufacture. However, the material mainly used for the internal combustion engine is made of a multi-layer structure after carding the fibers of the appropriate blend, and the final non-woven fabric through a process such as needle punching, heat press, chemical treatment, drying.

Comparing the filter performance of the filter paper and the nonwoven fabric, the filter paper has a low thickness and high density, low air permeability, and has an advantage in collecting efficiency while collecting particles according to the above-described method of manufacturing the media. In addition, there is a disadvantage in that a large area is consumed when applied to the filter material and excellent workability.

The nonwoven fabric has a high thickness and low density, high air permeability, and has a high collection life for collecting particles. However, the non-woven fabric has a low collection efficiency and a disadvantage in post-processability.

In the case of melt blown, it is possible to form ultrafine fibers, which are used as materials for various filters such as air purifiers. However, there is a problem in that they are difficult to use alone due to the disadvantages of strength, fiber detachment, and fiber breakage during bending.

Conventionally, as an air cleaning filter, US Pat. No. 6,315,805 laminates meltblown on filter paper, and two or more layers of fibers form a density gradient from the inflow side to the outflow side of the air, and the fibers of each layer are made of resin adhesive or ultrasonic wave. Disclosed is a filter medium combined using. However, combining these conventional meltblown fibers with filter paper has low thermal stability of the fibers due to the relatively low melting point of the meltblown fibers, which is very limited in post-processing, and has a painlessness of 5000L / m2 (at 200Pa). The use of relatively low weight melt blown (10-100 g / m 2, generally 25 g / m 2 or less) melt blown has the disadvantage of being very difficult to lamination, and the melt blown fibers have a relatively wide range of fiber diameters. In the case of small fiber diameters, the differential pressure increases rapidly as the amount of aeration increases.

The present inventors have diligently researched to solve the disadvantages of the conventional nonwoven media and to develop more superior media. As a result, one or more spunbond nonwoven fibers and an outlet layer (inner layer) of the air inlet layer (outer layer) will be described later. Filter media or melt blown layer is applied to filter media or melt blown layer, and the air blown and carbon trapping performance is excellent at the bonding strength, thermal stability, high flow rate, As a media with improved lamination workability, adhesiveness and filter efficiency during the manufacturing process, it has been confirmed that the present invention can provide an excellent air filter media in terms of collecting efficiency and amount of fine particles, which are disadvantages of existing media, and completed the present invention. It came to the following.

Accordingly, an object of the present invention is to provide an air filter material and a method of manufacturing the same, which can improve the life and the reduction of the carbon collection amount, which is a problem of the filter medium composed of conventional filter papers alone, and which can increase the efficiency, which is a problem of the nonwoven filter. It is.

A further object of the present invention is to use a spunbonded nonwoven fabric having a relatively large fiber diameter and even distribution, and having excellent bond strength between fibers as an external material, which is excellent in breathability in thermal stability and high flow rate and is a drawback and nonwoven filter which is a disadvantage of conventional filter paper. It is an object of the present invention to provide an air filter material having excellent efficiency and a method of manufacturing the same.

The present invention consists of two or more layers having a density gradient, one or more spunbond nonwoven fibrous layers on the air inlet side and a filter paper layer or meltblown layer as the final layer on the outlet side of the fluid, in particular two or more components with different melting temperatures. It provides a filter medium for air purification and a method of manufacturing the laminated melt melt layer consisting of.

As used herein, the term "final layer" refers to the layer of the air-inlet side or pre-layer, generally referred to as the out layer or the outer layer. It refers to the layer going out through, which is referred to as "Fine Layer" in the sense of a very dense layer of fibers, and also referred to in the art as an air (outlet) or an inner layer. Here, it should be noted that when the support layer is added to the fluid outlet side to the final layer as needed, it is called a rear end layer or a support layer, and this is not called a final layer.

The media of the present invention as described above is a lamination media that overcomes the disadvantages of the conventional efficacy, has a relatively large fiber diameter and even distribution, and by using a spunbond nonwoven fabric having excellent bonding strength between fibers, it is excellent in heat stability and high flow rate and dust There is an advantage that the collection amount and efficiency are excellent.

In order to achieve the above object of the present invention, at least one spunbond nonwoven fibrous layer is disposed on the pre-layer of the fluid, and the filter layer or meltblown as a fine layer, in particular, a melt melt having a different melting temperature The row is placed.

The media according to the invention comprises at least one outer layer (pre-layer or air-inlet layer) in the air inlet layer, the outer layer is preferably made of a spunbond nonwoven fabric.

The physical properties of the spunbonded nonwoven fabric used in the pre-layer depend on the required performance, but for internal combustion engines the weight ranges from 10 to 250 g / m 2, and the air permeability is 30 to 1500 cfm (pressure of 125 Pa and 20 cm 2), having a fiber diameter of 1 to 50 μm, a pore size of 10 μm or more, and one or more multilayer structures.

The material of the spunbond nonwoven fabric forming the outer layer is polyester, acrylic, polyethylene, polypropylene, viscose rayon, polyethylene terephthalate, polybutylene terephthalate, nylon, polyphenylene sulfide, polycarbonate or polyester glycol alone or these It can be used selected from the group consisting of mixed fibers, and can be used by spinning two or more mixed or spun bi-component (side by side, sheath / core, or divided yarn) form. The media according to the invention comprise as a final layer a filter paper or meltblown, in particular a meltblown consisting of release components with different melting points. In addition, the outer layer preferably has a density gradient, and the nonwoven fabric used to have a density gradient in the spunbond nonwoven fabric of the present invention preferably uses needle punching, chemical bond, thermal bond, spunbond, or bulky meltblown. can do.

Among the filter papers or melt blown used in the final layer, in particular, the physical properties of the melt blown (preferably composed of two or more components having different melting points) are preferably composed of about 5 to 40 wt% of the total filter weight. It is desirable to have a pore size in the range of 20 to 150 μm, a weight in the range of 10 to 350 g / m 2, an air permeability in the range of 10 to 800 cfm (at a pressure of 125 Pa), and a fiber diameter in the range of 0.5 to 30 μm. .

The filter paper has media having a pore size in the range of 3 to 80 μm, a weight in the range of 30 to 350 g / m 2, an air permeability in the range of 3 to 150 cfm (at a pressure of 125 Pa), and a fiber diameter in the range of 5 to 50 μm. As the cellulose fiber alone or made of synthetic fibers, preferably, synthetic fibers include, but are not limited to, PET or PVA.

The meltblown nonwoven fabric of the final layer may be selected from conventional meltblown, in particular polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, nylon, polyphenylene sulfide, polycarbonate (PC) And two or more selected from the group consisting of polyester glycol (PETG) and spun or spun into bi-component (side by side, sheath / core, or split yarn) to form a heterogeneous melting point fiber. And low melting point PET-high melting point PET, low melting point PET-high melting point PBT, low melting point nylon-high melting point nylon, PBT-nylon and the like.

It is preferable to use a method of laminating each fibrous layer by ultrasonic fusion or heat-resistant hot-melt such as polyamide, polyester, polyurethane, and moisture-curable polyurethane. It is preferable to use two or more of the above methods in combination.

In addition, each layer of the media according to the present invention may be carried out using a needle punching method, a bonding method using a low melting point resin or a water-soluble resin alone or in combination. In addition, it is preferable to use a heat treatment step in a post process so as to facilitate adhesion. The bonding process by heat treatment is performed by melting the meltblown web using a heat treatment at 100 to 300 ° C. using a fusing oven, a belt press, a calender, or hot air. The low melting point resin present in the melt is bonded. At this time, as a result of the heat treatment, the release polymer fibers having different melting points are twisted and distorted by heat, and the porosity is improved than the existing media, so that both filter efficiency and lifespan are increased. Moreover, the above approach simplifies the process for laminating each nonwoven layer and can improve the secondary problems that occur during lamination. In the past, the media adhered by needle punching impeded the filter performance by generating holes in the media by the needle, but when the heat treatment process was performed after punching the needle by the method of the present invention, the pores generated by the needle were in the molten fibers. It is recovered to some extent, and no separate adhesive resin is required in the process, and the melt blown performs the adhesive function. Of course, a chemical resin such as hot melt may be used as needed to maximize the adhesion.

The media according to the present invention may further preferably include a support at the rear end of the meltblown layer, if necessary. The support may be made of a conventional nonwoven fabric, and a weight having a weight of 5 to 60 g / m 2 may be preferably used.

Such nonwoven media can also be produced using conventional manufacturing techniques. Examples include spun bonds, spunlaces, needle punchings, chemical bonds, thermal bonds, air-laids and meltblowns. Process or process can be used.

The total weight of the finally prepared composite material is most preferably 150 ~ 500 g / ㎡, pore size (pore size) 10 ~ 100 ㎛, air permeability is 10 ~ 150 cfm (at a pressure of 125 Pa).

In still another aspect, the present invention provides a method for producing the media as described above.

As for the manufacturing method of the media which concerns on this invention, as an example thereof is briefly shown to FIG. 1 and FIG. 2, it can manufacture by combining a normal manufacturing method. In embodiments of the manufacture of such multilayer media, as illustrated in FIGS. 3 to 5, a filter paper layer or a meltblown layer is applied as the final layer to which at least one spunbond nonwoven fabric is applied to the outer layer and / or A manufacturing method for bonding the support layer may be employed, and the outer layer may take the form of a nonwoven fabric of a spunbond alone or a nonwoven fabric and a spunbond nonwoven fabric.

More specifically, the method for producing a filter consisting of a spunbond nonwoven fabric and filter paper according to the present invention

a) respectively conveying at least one spunbonded nonwoven and filter paper from the rolled roll,

b) spray spinning or dot type application of an adhesive (hot-melt or water soluble binder) to the spunbond nonwoven fabric and / or filter paper layer as needed,

c) laminating the media applied with the adhesive and the other media with a tension roll;

d) fusion by ultrasonic welding and

e) winding up the media adhered by fusion;

It includes.

In addition, the method for producing a filter medium consisting of a spunbond nonwoven fabric and a meltblown (preferably meltblown composed of a release component) filter paper according to the present invention is

a) respectively conveying at least one spunbonded nonwoven and meltblown from the rolled roll,

b) spray spinning or dot-type adhesive (hot-melt or water-soluble binder) onto the spunbond nonwoven fabric and meltblown layer, if necessary, as well as tension rolls on the adhesive-coated media and other media Laminating by,

c) if necessary, laminating the spunbond nonwoven or meltblown layer and then joining the web by a plurality of needles (needle punching nonwoven bonding method)

d) fusing the laminated media by a fusing oven, belt press, calender or hot air at 100-300 ° C., and

e) winding the bonded media

It includes.

When using a conventional calender, fusing oven or belt press, etc., there is a problem that the low melting point fiber is used in a large amount on the adhesive surface of the outer layer and the heat treatment temperature is very high. However, when manufacturing the filter medium for air purification in the above manner, In the meltblown, the low melting point resin is arranged in the form of ultrafine fibers, thereby enabling adhesion at low temperatures and minimizing the use of low melting point fibers in the outer layer. In addition, there is no need to use a separate adhesive, such as productivity and cost savings.

In addition, when the needle punching method is used, the breakage of the fiber, which is a fatal disadvantage in filter efficiency, has occurred, but in the above method, when the needle punching method is used in parallel to increase the adhesive force, a calender, fusing oven or The breakage can be restored by using the belt press method, and the low melting melt blown is melted to increase the bonding force with the nonwoven fabric layer. In addition, since the high melting point fiber is included, pore blockage due to the film formation of the fiber is minimized, and the bonding force and porosity can be adjusted according to the blending ratio during the manufacture of the meltblown.

The media according to the invention can be bent. Accordingly, the bending process is performed in the order of bending the melt-blown media to suit the shape to be used, cutting for each size, and curing for a predetermined time at a predetermined temperature in a conventional manner. In this case, the curing process may be omitted depending on the resin and the process used. Accordingly, the present invention provides, in a further aspect, a filter element which is manufactured by bending the media. The filter element may be a star-type or a flat panel type.

In the process of using a bending machine for the molding as described above, the bending machine may use a rotary, mini frit, knife bending machine, etc. Among them, it is advantageous to be able to bend the media using a knife bending machine, the bent shape The set curing temperature is set at 130-180 ° C., which is almost similar to that of conventional nonwoven fabrics.

The total weight of the finally prepared composite material is most preferably 150 ~ 500 g / ㎡, pore size (pore size) 10 ~ 100 ㎛, air permeability is 10 ~ 150 cfm (at a pressure of 125 Pa).

<Examples>

Hereinafter, the present invention will be described in more detail with reference to Examples. However, these are merely exemplary and are not intended to limit the present invention to them.

The performance of the media obtained after performing each bonding method differently using the following raw material costs is shown below. The dust used in the test method was AC fine. The test flow rate was 25 ㎥ / min, the filtration area was 176.6 ㎠, and the dust input amount was 0.5g / 2min.

 In addition, in order to measure the carbon capture performance, the filter area: 216cm2, the flow rate: 1.6㎥ / min, the end condition: the initial pressure + 300mmAq, the alcohol lamp flame size: 15 cm, the distance between the filter paper and the alcohol lamp: 440 The condition of cm was used.

Examples 1-5 and Comparative Examples 1 and 2

As shown in Table 1 below, the filter paper was made of wood pulp used in an existing vehicle, and was manufactured by a process such as dissociation, confession, grassland, drying, and impregnation, which is a general filter paper manufacturing method. In addition, the melt blown and filter paper showed the physical properties of the media laminated by ultrasonic wave, and the melt blown (melt blown composed of two or more components having different melting points) New properties). In addition, the physical properties of the needle punching media prepared by the carding-needle punching-calendering-winding method are also shown.

Properties of Media Used Ingredients Weight (g / m ² ) Thickness (mm) Fiber diameter (㎛) Aeration (cfm, 125Pa)  Media material Filter paper 125 0.59 > 10 90 Cellulose Meltblown + Filter Paper 150 0.73 - 88 PBT + Cellulose Spunbond 1 15 0.08 9-30 3400 PET Spunbond 2 25 0.11 9-30 1200 PET Spunbond 3 40 0.17 9-30 900 PET  Melt blown 50 0.38 > 1 μm 250 PBT (IV 0.8) 50% PET (IV 0.8) 50% Needle Punched Nonwovens 200 2.23 300 PET / VR Among the abbreviations, PET stands for polyethylene terephthalate [Poly (Ethylene Terephthalate)], PBT stands for polybutylene terephthalate [Poly (Butylene Terephthalate)], and VR stands for viscose rayon.

 Each of the media shown in Table 1 was laminated by a conventional method of heat treatment after ultrasonication, hot-melt, or needle punching, and the performance of these media was compared. In addition, the performance of the filter media alone and the filter medium and the filter paper and the melt blown lamination media were compared with the results, and the results are shown in Tables 2 and 3.

Comparison of Properties of Media with Final Layer Filter Aeration (cfm) Dust collection initial efficiency (%) Dust collecting boil efficiency (%) Dust collection life (min) Carbon capture amount (mg) Carbon capture efficiency (%) Comparative Example 1 Filter paper 95 99.14 99.75 6 17.6 95.14 Comparative Example 2 Meltblown + Filter Paper 88 99.21 99.79 12 22.5 95.22 Example 1 Spunbond 1 + Filtration 93.2 99.19 99.77 10 minutes 18.4 95.23 Example 2 Spunbond 1 + Spunbond 2 + Filter Paper 90 99.27 99.89 16 minutes 24.8 96.1 Example 3 Spunbond 3 + Filter Paper 89 98.25 99.84 14 minutes 23.9 95.7

As shown in the table, comparing the physical properties of the filter paper of Comparative Examples 1 and 2 and Example 1, the filter medium of Example 1 laminated 15 g / m ² spunbond nonwoven fabric on the same filter paper by ultrasonic welding method is dust The efficiency of the collection effect is almost the same, but there is a significant increase in the amount of collection, that is, the lifetime. Compared with the meltblown medium of the comparative example 2, it is judged that the thing whose lifetime is slightly short is due to the weight difference. In addition, it can be seen that the amount of carbon capture increased significantly.

In addition, when comparing the media of Examples 1 to 3, it can be seen that the media of increasing the weight of the spunbond from 15 g / m ² to 40 g / m ² is very excellent in both dust and carbon collection effect, spun of the same weight Example 2 applying the bond media to the layered structure showed better performance. In other words, spunbond nonwoven fabrics can be used as prefilters on the outer layer of filter paper, such as media with meltblown nonwoven fabrics on the outer layer, and the effect is more than that of meltblown on the outer layer in consideration of price competitiveness, workability and post processing I think it's excellent.

Subsequently, the spunbond and the melt blown are needle punched-thermal calendered-winding process, that is, lamination by the needle punching method, followed by surface treatment of the melt blown using the thermal calendered method to prepare the media (Example 4) When fabricating a needle punch nonwoven fabric which carries out the process of carding-needle punching-calendering-winding, spunbond and melt blown are inserted into the needle punching shear to prepare a filter medium (Example 5) Table 3 shows. Table 3 below shows the results of comparing the physical properties of the media using the meltblown as a final layer.

Aeration (cfm) Dust collection initial efficiency (%) Dust collecting boil efficiency (%) Dust collection life (min) Carbon capture amount (mg) Carbon capture efficiency (%) Example 4 Spunbond 3 + Melt Blown 87 98.95 99.41 12 minutes 18.4 95.93 Example 5 Spunbond 3 + Needle Punch Nonwoven + Melt Blown 87 98.92 99.35 26 minutes 94.2 96.18

As shown in Table 3 above, the filter performance against dust and carbon was compared to the filter medium of Example 3, which used the melt blown in the final layer, as compared to the filter medium of Example 3, which used the filter paper in the final layer. 3 was found to be better. However, this may be due to the weight difference between the filter paper and the meltblown used in the final layer. Comparing the media of Example 5 to which the 200 g / m ² needle punch nonwoven fabric is applied to that of Example 3, it can be seen that the case of Example 5 significantly increased the carbon capture effect as well as the lifetime for dust collection.

As described above, the filter medium according to the present invention can improve the life (capture amount) decrease, which is a problem when using the filter paper alone, and can increase the efficiency, which is a problem of the nonwoven filter. In addition, the use of spunbond non-woven fabric with high thermal stability is very good thermal stability, which is a disadvantage of the existing lamination media, and is not only in post-processing, but also in lamination workability and adhesiveness and filter efficiency during the media manufacturing process. In addition, the carbon capture performance, which causes malfunction of the sensor due to the automatic automation of the internal combustion engine system, is very excellent, and thus it can be mainly applied to internal combustion engines and especially hybrid vehicles.

Claims (12)

A filter media for air purification comprising two or more layers having a density gradient and comprising at least one spunbond nonwoven fibrous layer on the air inlet side and a filter paper layer or meltblown layer as the final layer on the air outlet side. The method of claim 1, wherein the spunbond nonwoven fiber layer has a weight of 10 ~ 250 g / ㎡, a ventilation of 30 ~ 1500 cfm (at a pressure of 125 Pa and an area of 20 cm 2), a fiber diameter of 1 ~ 50 ㎛, A filter medium for air purification, wherein the pore size is 10 μm or more. The method of claim 1, wherein the spunbond nonwoven fiber layer is polyester, acrylic, polyethylene, polypropylene, viscose rayon, polyethylene terephthalate, polybutylene terephthalate, nylon, polyphenylene sulfide, polycarbonate and polyester glycol Filter media for air purification that is spun by spinning two or more resins selected from the group consisting of or in a bi-component (bi-component) form. The method of claim 1, wherein the melt blown layer is selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, nylon, polyphenylene sulfide, polycarbonate, and polyester glycol A filter medium for air purification, in which the above resin is mixed and spun or spun in the form of a bicomponent. The meltblown layer of claim 1, wherein the meltblown layer has a pore size in the range of 20-150 μm, a weight in the range of 10-350 g / m 2, an air permeability in the range of 10-800 cfm (at a pressure of 125 Pa), and 0.5- A filter medium for air purification, having a fiber diameter in the range of 30 μm. The filter paper layer of claim 1 wherein the filter paper layer has a pore size in the range of 3 to 80 μm, a weight in the range of 30 to 350 g / m 2, an air permeability in the range of 3 to 150 cfm (at a pressure of 125 Pa), and 5 to 50 μm. A filter medium for purification comprising cellulose fibers alone or synthetic fibers having a fiber diameter in the range. delete delete The filter medium of claim 1, further comprising a support at a rear end of the meltblown layer. A filter element, which is prepared by bending the filter medium according to claim 1. a) respectively conveying at least one spunbonded nonwoven and filter paper from the rolled roll, b) spray-spraying or applying a dot type adhesive to the spunbond nonwoven fabric and filter paper layer, c) laminating the media applied with the adhesive and the other media with a tension roll; d) fusion by ultrasonic welding and e) winding up the media adhered by fusion; Method for producing a filter media for air purification comprising a. a) respectively conveying at least one spunbonded nonwoven and meltblown from the rolled roll, b) spray spinning or dot type spraying an adhesive (hot-melt or water-soluble binder) on the spunbond nonwoven fabric and the meltblown layer, and laminating the adhesive-coated media and other media with a tension roll; step, c) laminating the spunbond nonwoven or meltblown layer and then joining the web by a plurality of needles, d) fusing the laminated media by a fusing oven, belt press, calender or hot air at 100-300 ° C., and e) winding the bonded media Method for producing a filter medium for air purification, comprising a.

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